I have a 196? 50HP merc and the tachometer needle does not drop under 2000 even when the boat is off. When I am at WOT it shows 5500 so I am not sure if it is 5500 or 3500. Can I calibrate this or?
Check the back of your tach for a rotator switch. Make note of what position it is, and then rotate it back and forth a few times. Reset to the original position. Start your motor on muffs. should read about 850-1000 rpms. if it doesn't, shut it down, and try each position on the tach until you find the right one. Also, clean your contacts.
The tach will not always go to 0 when shut off, but should zero out when the key is turned to on. What brand of tach do you have? Its not an automotive tach is it? They are not compatible with outboards.
There is usually a selector switch on the back to configure it to the motor. Don't confuse an auto tach with the 4, 6 or 8 cyl settings. They do not apply to outboards.
